Furnace-grate.



W. MCCLAVE.

FURNACE GRATE. y APPLICATION FILED MAR-23.19\6. 1,259,646, Patented Mar. 19,19i8.

4 SHEETS-SHEET 1.

W. McCLAVE.

FURNAGE Gam.

APPLICATION' FILED Mums. me.

Batented Mar. 19, 1918.

4 SHEETS-SHEET 2.

W. MCCLAVE.

FURNACE GRATE.

APPLICATION FILED MAR.23. l9i6.

l ,25 9, 646 Patented Mar. 19, 1918.

W. c LAVE. FUR GRATE.

PPucATmN FILED mima 1 1,259,646. l A m' Patented Mar.19,'1918.

4 SSSSSSSSSS ET. 4.

.sas

WILLIAM MCCLAVE, or vsonairrronJ rnnNsYnvAivIa, assreivon 'ro mconavn-,Bioons COMPANY, or SCRANTON, rnnnsrnvama, a .eonronarroiv or rnivivsYLvANIA.

FURNACE-GRATE.

Specification of Letters Patent.

Patented Mar. 19, 1918.

Application led March 23, 1916. Serial No. 86,292.

To all whom t may concern.'

Be it known that I, lWILLIAM McCLAvn, a citizen of the United States, residing at Scranton, in the county of Lackawanna and State of Pennsylvania, have invented certain new and useful Improvements'in Furnace-Grates; and I do hereby declare the follow-ing to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specification.

This invention relates to improvements in furnace grates and the particular object of the invention is the provision of an irnproved furnace grate for the burning of very small sizes of coal.

In the burning of small size coal, especially grades of anthracite as small as or smaller than what is known as buckwheat, it is absolutely necessary that the draft be equally and uniformly distributed over the entire fuel burning area of the grate to obtain proper combustion of the fuel. The small size of the coal requires the air passages of the grate to be restricted in size and, to obtain a uniform draft throughout the grate, the air passages must be uniform in size and equally distributed. rlhere must be no air passages of substantially larger area than the others, and for this reason, it was long thought that the only successful solution of the air distribution problem was to employ a stationary grate, since in all prior arrangements, the provision of a dumping section resulted in elongated air passages at the joints between adjacent sections, so as to admit blasts of air in large volume at the joints. The elongated air passages allow sifting of the unburned fuel to the bottom of the furnace, resulting in considerable waste, and the large volume of air which finds entrance to the firebcd seriously disturbs the fire. so as to make it practically impossible to obtain the best results. The stationary grate. while satisfactorv so far as the air distribution is concerned, is very disadvantageous in that it is extremely difvticult to clean.

According to the present invention, a novel grate construction is provided. in which a section of the grate. preferably a section intermediate stationary sections, is movable to permit dumping of the fire and cleaning of the grate. and. at the same time the @hamster .of the. joints between the dumping section and adjacent stationary sections is such that no elongated ai-r passages or gaps of substantially larger size than the air passages of the grate are formed aty the joints and the equal distribution of the draft is preserved throughout the grate.

'Other objects of the invention are to generally improve the construction of furnace grates, as will appear from the ensuing detailed description of a structural embodiment of the invention in a preferred form. The novel features of the invention will be pointed out in the claims at the end of the specification.

ln the accompanying drawings:

Figure 1 is a longitudinal sectional elevar tion of a' furnace provided with a grate con structed in accordance with the `present improvements.

Fig. 2 is a fragmentary pla-n view on an enlarged scale of the dumping section of the grate and an adjacent stationary section.

Fig. 3 is a section taken transversely of the dumping section of the grate, on the line 3 3 or rig. 2.

Fig. t is a section taken longitudinally of the dumping section of the grate. on the linev l-ec of Fig. 2, the adjacent portions of the front and rear stationary sections being indicated byv dotted lines. i 4

Fig. 5 is a transverse section on the line 5-5 of Fig. 1.

Fig. 6 is a transverse section on the line 6 6 of Fig. l.

Fig. 7 is a fragmentary plan view of the means for tilting the intermediate dumping section of the grate.

Fig. 8 is a plan view on a reduced scale of the interior of a furnace and grate.

Fig. 9 is a fragmentary sectional elevation on an enlarged scale taken on the line 9-9 of Fig. 1 and looking toward the front of the furnace.

Fig. 10 is a longitudinal sectional elevation of one of the stationary bars of the inf termediate section of the grate.

Like characters of reference in the several figures indicate the same parts.

In the form illustrated in the accompanying drawings. the furnace is of the battery. time, that is to sav. the furnace has a ser-ies of fireboxes arranged in a line one after the other, the portion of the furnace shownbe.- ing the firebox at the eXtreme left hand end ofthe furnace, anflliavitlg .a front Wall l.,`

a side wall 2, a middle wall 3, separating the iirebox from the next adjacent one to the right, and a rear wall 4 connecting the side and middle walls 2 and 3. As shown most clearly in Fig. 8, the front wall 1 of the furnace is provided with feed door openings 5, 5, through which the rebox or inner chamber 6 maybe supplied with fuel and a tool inserted to stir the fire. The present invention is, however, in no way concerned with the particular type of furnace illustrated, Vbut in the novel grate construction, and hence it will be understood kthat the grate may be readily applied to other types of furnaces without departing from the spirit of the invention.

At the front end of the firebox and extending transversely across the front wall 1 is a dead plate 7.. The front end of said dead plate rests on an inwardly-projecting ledge carried by the furnace wall 1 and located just beneath the bottom edge of the feed door openings 5, 5, and the sides of the dead plate are formed into projections 8. which extend into suitable recesses 9 in the side and middle walls of the furnace and thereby hold said dead plate inplace. To permit growth of the dead plate transversely, the recesses 9 in said side and middle walls are deeper than the projections 8. Mounted on the dead plate 7 is a firebrick section 10, the top of which is preferably flush with the bottom edge of the feed door openings 5, 5, as shown in Fig. 1.y rlhe rear end of the firebrick section 10 is preferably curved, as. at'11, and terminates short of the rear end of the dead plate 7. Mounted` on the rear end of the dead plate is a transverse bar12, the upper surface of which will hereinafter appear.

lies somewhat below the top of the dead plate 7,`whereby.a shelf or ledge is provided for the support of the forward end of the grate, as will hereinafter appear. Y

Supported in suitable recessesl formed inthe side and middle walls 2 and 3 of the furnace are transverse bearer bars 14 and 15. The rear end of the dead plate 7 isformed with a depending vertical flange 16, andthe forward bearer bar 14 is connected to said depending flange 16 by means of longitudinal strut and tension rods 17. The rods 17 may be adjusted by means of nuts 18, as shown, and serve to prevent the bearer 14 from springing up, when the intermediate dumping section of the grate is tilted, as The rear wall 4 of the furnace is provided with a recess 19 receiving a iirebrick section 20, as shown in Fig. 1. At the lower edge of the recess 19, is a transverse bracket bar 21y having forwardly and rearwardly projecting horizontal'portions 22 and 23 respectively and a vertical depending portion 24 which may be secured to the inner side of the rear wall 4,

'in any suitable manner. The rearwardly projecting portion 23 of the bracket bar 21 projects between the firebrick section 20 and the bottom of the recess 19, andthe forwardly projecting portion 22 of the bracket bar supports a transverse bar 25 the upper surface of which is preferably in line with the upper surface of bar 12, said bar 25 forming a shelf 0r ledge on which is supported the extreme rear end of the grate, as shown in Fig. 1. Connecting the'vertical portion 24 of bracket bar 21 and the rear bearer bar 15 are longitudinal adjustable strut and tension rods 26 which assist in maintaining rigidity of the rear bearer bar.

A grat-e constructed'in accordance with the present invention preferably consists of three main sections or divisions, the front section 27, intermediate section 28and rear section 29. The front and rear separated sections 27, 29, are stationary, front section 27 being supported by ledge 12l and forward bearer bar 14, and rear section 29 being supported by ledge 25 and rear bearer bar 15, The upper surfaces of the front and rear ends of the respective front and'rear grate sections areV downwardly beveled, as shown at 30, the bevels meeting the fiatV under sides of the grate sections at the extremev ends of the sections. Preferably, the forward end'of grate section 27 terminates to the rear of the forward extremity of ledge 12, and similarly the rearward end of grate section 29 terminates in front of the rearward extremity vof ledge 25. This construction allows for the normal growth of the sections 27, 29, `toward the front and rear walls of the furnace, after prolonged use. Each stationary section of the grate is .pro-

vided with spaced depending vertical flanges 30, running longitudinally of the respective sections, and between. adjacent flanges' are preferably two longitudinally-extending series of restricted air holes or passages 31, the air holes of one series being staggered with relation to the air holes of the other series. Extending longitudinally betweenV the pairs of series of air passages and on the upper surface of the grate are ribs 32, these ribs being located above the verticall flanges 30, as shown more particularly in Fig. 5.

The intermediate dumpingl section'28'extends transversely of the furnace vand is located between the proximate ends of the stationary sections 27, 29, and with its fuel-supporting area or upper surface substantially in Vthe same plane as the fuel supporting areas of the stationary Sections. According Y to the present invention, the intermediate section 28 may be tilted wholly'beneath the fuel-supporting areas of the stationary sections7 when it is desired to dump the fire and clean the grate, and thev joints between the proximate edges of the stationary sections and the dumping Section are of such a nature Y that, while, no interference is oered to the nesegeae,

tilting movement of the du'mpi'ngfsection,

' ing sections relatively to each other is permitted.. As shown, the rearward end of section 27 and the forward end of section 29 are curved or beveled downwardly as at 33, and the said ends of the sections are also curved or beveled upwardly, as at 34. The upper extremity of a curved portion 34 is inwardly offset fromy the lower extremity of a curved portion 33, and the extremities of said curved portions are connected by a horizontal surface 35. This construction provides overhanging or overlapping edges at the proximate ends of the stationary sections. The opposite transverse edges of the dumping section Q8 are curved or beveled downwardly as at 36 and beveled upwardly as at 37, the upper extremities of portions 37 being outwardly offset from the lower exl tremities of portions 3G and said extremities being connected by horizontal surfaces 37 The horizontal surfaces 37 are designed to underlap and engage the horizontal surfacesV 35 of the respective stationary sections 27 and 29, thereby pe initting adjacent edges of the grate to grow toward each other, while at the same time a tight joint is formed, when the parts are in normal position with the intermediate sections bridging the front and rear sections, preventing the entrance of air at thejoints. If, however, it be desired to permit the entrance of equally distributed restricted volumes of air at the joints between adjacent edges, so as to preserve the equal distribution of the air .hrouhout the grate, the underlapping edges of the dumping section 2S may be pro-vided with spaced vertical slots 37a, as shown in l*1 ig. Q. It will be noted that the overhanging edges of the stationary sections cover portions of the slots 37, and the said slots willbe of such breadth that the uncovered portions Of the slots will be of substantially the Same size as the air holes in they stationary sections of the grate.

In the present instance, the intermediate dumping section 28 is preferably made up of a plurality of grate bars extending longitudinally of the grate and lying side-byside. As shown in Figs.' 2 and 3, the longitudinal edges 38 of alternate bars 39 are designed to underlap the adjacent longitudinal overhanging edges 40 of the other bars 41, the joints at. the proximate longitudinal edges of the bars being similar in construction to the joints at the proximate transverse sides of the dumping section and the stationary sections, whereby growth of the several bars transversely of thev grate is permitted. The undei-'la-pping longitudinal edges 3S'may be also provided-with slots 42 similar f tothe slots 37a, hereiiibefore described'. The

fuel supporting area of the barsmakingnp the intermediate dumping section may be reinforced by longitudinally-extending ribs 43, and the bars are provided with series of restricted air holes 44 of the same size and spacing as the air holes in the stationary sections 27, 29. The bars are further reinforced by longitudinal vertical depending lia-nges 43a.

The bars of the intermediate dumping section 28 are adapted to be tilted in unison wholly beneath the fuel supporting areas of the front and rear stationary sections 27, 29, by means of the following mechanism: The forward bearer bar 14 is provided with spaced bearing brackets 44 supporting shafts 45 asr shown more particularly in Figs. 6 and 7, and the tilting bars are provided with forwardly and downwardll projecting arms 46 mounted on the shafts 45. Two adjacent pairs of bars 39, 41 are mounted by the arms 46 on a single shaft 45, as shown. Rotatably mounted in brackets 49 secured to bearer bar 14 is a transverse shaft 50 havingl links 51 fixed thereto. The links 51 Corresponding in number with the grate. bar sections 39, and the free ends of saidl links are provided with rollers 51a adapted;y

to eneaoe the central longitudinal flanges 43b n D C 23 of the respective bars 39. Depending fromA shaft 50 is a curved link 52, the lower end of which is pivoted to an operating bar 53v extending longitudinally of the furnace and projected through an opening in the front,- wall thereof. Preferably, operating bar 53 is in two sections adjustably held together by a turnbuckle Pivoted to a bracket 55 supported on the side of the front wall 1 of the furnace is an operating lever 56, and the forward end of the bar 53 is pivoted to said lever.

With the above described construction, if operating lever is pulled outwardly from the furnace, the reciprocatory motion thereby imparted to bar will oscillate shaft 50, in the direction indicated by the curved arrow of Fig. 1. As a result, links 51 will be tilted downwardly in unison, so as to permit the grate bars mounted on shafts 45 to tiltin unison, the central flanges 43b riding on the rollers 5N. rllhe tilting of the bars of the dumping section 2S is readily accomplished by reason of the improved construction of the joints hereinbefoi'e described. lllhen the dumping section 28 is shifted back into position wherein the fuel supporting areas of the three sections of the grate are in substancial alinement by moving lever 56 toward the front wall of the furnace, the joints formed between the stationary sections and the dumping section are tight enough to prevent the passage of ir, except through the if'ertical slots hereinbefore described. In the type of furnacel illustrated a blast 0fy air is admitted to the iirebox through an opening 57 in the bottom of the furnace.V

The grate bars 58, at the extreme sides of the intermediate section of the grate, are preferably ,not movable, but secured to the bearer bars 14, 15, by front and rear braces 59, 60, as shown in Fig. 10. The forward brace 60 is bolted to the forward bearer bar 1l and the rear brace 59 rests on a ledge 61 formed on the rear bearer bar 15. The joints between the stationary bars 58 and the movable bars of the intermediate section are of the hereinbefore described type, with the longitudinal edges of the stationary bars overhanging the proximate longitudinal edges of movable bars. The stationary bars may be set within longitudinally extending recesses 62 formed in the side and middle walls of the furnace, permitting growth of the bars t-ransversely.

Y As shown, the recess in the side wall is somewhat deeper' than the recess in the middle wall.

lVhat is' claimed is 1. A furnace grate of the class described, comprising front and rear spaced stationary grate sections, each stationary section being' provided with an overhanging edge disposed oppositely to the overhanging edge of the other stationary section, and an intermediate dumping section adapted normally to bric ge said front and rear stationary sections, said intermediate section being adapted to engage the overhanging edges of the stationary sections, and tiltable on a t-ransverse axis wholly beneath the fuel supporting areas of thel stationary sections, and means for so tilting said intermediate dumping section. Y

2. A furnace grate of the class described, comprising front and rear stationary secytions, an intermediate dumping section ltion having its opposite edges formed to unbridging the front and rear sections, said intermediate section being composed of a plurality of separate bars lying side by side and formed with lapping proximate edges, said bars being mounted on a transverse axis relatively to the front and rear stationary sections, and means for tilting said bars in unison beneath the fuel supporting areas of the front and rear sections.

3. A furnace grate such as described, embodying front and rear spaced-apart stat-ionary Ysections having overhanging proximate edges, an intermediate dumping secderlap the overhanging edges of the stationary sections, and means for tilting said intermediate section wholly beneath the fuel supporting areas of the stationary sections.

4. A furnace grate such as described, embodying front and rear spaced-apart stationary sections having equally spaced air passages and provided withvoverhanging proximate edges, 'an intermediate dumping section having its opposite edges formed to underlap the overhanging'edges of the stationary sections, slots in said opposite edges of the intermediate section forming air passages of substantially the same size as the air passages in the stationary sections when the dumping section is in alinement with the latter, and means for tilting the'dumping section Wholly beneath the fuel supporting areas of the stationary sections.

5. VA furnacegrate such as described, embodying front and rear spaced-apart stationary sections having over-hanging proximate edges, an intermediate dumping section adapted normally to bridge said front and rear sections and having its opposite edges formed to underlap and engage the overhanging edgesV of the stationary sections, a series of air passages in the edges of the intermediate section, andtmeans for tilting the intermediate section wholly beneath the fuel supporting areas of the 'front and rear sections.

6. A furnace grate such as described, embodying a stationary grate section having its fuel supporting area lying substantially in a horizontal plane and provided with an overhanging edge, a movable grate section having its proximate edge adapted to underlap and engage the overhanging edge Yof said stationary section and with the fuel supporting area of the movable grate Vsection adapted to lie normally in substantially the same plane as the stationary section, and means for tilting said vmovable section wholly beneath the fuel supporting area of the stationary section.

7 A furnace grate such as described, embodying a stationary grate section having uniformly spaced air passages of uniform size andan ,overhanging edge, a movable grate section having its proximate edge formed to underlap and engage the overhanging edge of said stationary section, the edge of the movable section having spacedapart slots of dimensions to fornrair passages substantially uniform in size with the air-,passages in the stationary section, and means for tilting the movable section wholly beneath the fuel supporting area of the stationary section.

8. The combination with a furnace, front and rear stationary grate sections having their oppositely disposed edges'spaced to form an intermediate dumping outlet, means for supporting the front and rear ends of said stationary grate sections, intermediate transverse bearer bars supporting the stationary sections beneath the fuel supporting areas of the latter and with the oppositely disposed edges of the front and rear sections extending respectively rearwardly and forwardly of` the' transverse bearer bars, an Y inter-mediate dumping section' adapted normally to engage 'the extending edgesv of Lai-9,646

the stationary sections beneath the fuel supporting area of the latter and thereby adapted to bridge the intermediate dumping outlet, and means for tilting said intermediate dumping section about a transverse axis relatively to the front and rear stationary sections.

9. The combination With a furnace having transverse supporting ledges projecting inwardly from the front and rear Walls thereof, of front and rear stationary grate sections having their proximate edges spaced apart to forni an intermediate dumpingV outlet, and their front and rear edges overhanging said transverse supporting ledges, transverse bearer bars supporting the stationary sections beneath the fuel supporting areas of the stationary sections and With the proximate ends of the front and rear sections extending respectively rearwardly and for- Wardly of the transverse bearer bars, an intermediate dumping section adapted normally to engage the proximate ends of the stationary sections to bridge the intermediate dumping outlet, and means for tilting `said intermediate dumping sections about a transverse axis.

l0. The combination With a furnace, of a grate embodying front and rear spacedapart stationary sections having their respective front and rear ends supported by the front and rear Walls of the furnace, transverse bearer bars supporting the stationary sections adjacent the proximate ends of the latter, an intermediate grate section composed of a plurality of tiltable grate bars and stationary bars at the sides of the tiltable bars mounted on the transverse bearer bars and parallel with the side Walls of the furnace, and means for moving the tiltable bars in unison about a transverse axis.

l1. rllhe combination with a furnace, of a grate embodying front and rear'spacedapart staticnary sections having their respective front and rear ends supported by the front and rear Walls of the furnace, transverse bearer bars supporting the stationary sections adjacent the proximate ends of the latter, an intermediate grate section composed of a plurality of tiltable grate bars and stationary bars at the sides of the tiltable bars mounted on the transverse bearer bars and parallel with the side Walls of the furnace, and means for moving the tiltable bars in unison about a transverse axis and Wholly beneath the fuel-supporting areas of the stationary sections.

WILLIAM MCCLAVE.

(Iopies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

